Retractable folding steps



United States Patent [72] .lnvento r Charles A. Dohrman I P.0. Box 128,Sunnyside, Washington 98944 I [21] Appl. No. 785,272 [22] Filed Dec. 19,1968 [45] Patented Dec. 8,1970

[54] RETRACTABLE FOLDING STEPS 12 Claims, 14 Drawing Figs.

[52] U.S.Cl. 182/97 [51] 1nt.CI. E06c1/383 [50] Fieldof Search 1 82/96,97,

[56] 9 References Cited UNITED STATES PATENTS 666,566 l/ 1901 Sherman182/96 1,419,834 6/1922 Fellows l82/1 2,498,375 2/1950 Moore 182/161 7/1966 Schoefi'ler Primary Examiner-Reinaldo P. Machado Attomey-Shoemakerand Mattare ABSTRACT: A support means includes a fixed portion carryinga pivot pin and an arcuate guide s1ot.'The support means includes asecond portion having a first part connected with said fixed pivot pinand a second part which is slidably guided by said arcuate slot. A pairof spaced upper side rails and a pair of lower spaced side rails areeach swingably supported by the second portion of the support means. Aplurality of steps are movably interconnected with the upper and lowerside rails and means is provided for holding the arrangement in itsstored position.

PATENIED nu: 8 I970 SHEET 1 UF 3 CHARLES A. DOHRMAN BY Um ATTORNEYSPATENTEU on: 81976 3.54556? SHEET 2 0F 3 100 '0 IO LL/ Ill I I I4INVENTOR CHARLES A. DOHRMAN 3 022 BY Mk1 M Z SZ Z 26 ATTORNEYSPATENTEDUEC 8|97U 3545567,

Fig. l0.

INVENTOR CHARLES A. DOHRMAN ATTORNEYS l membranes FOLDING STEPSBACKGROUND OF THE INVENTION The present invention relates to a foldingstep structure which is adapted to be supported in a retracted compactarrangement, and then selectively swung into operative position toprovide a rigid sturdy step construction.

The present invention is adapted to be employed in many applicationssuch as with campers, trailers, mobile homes, flatbed trucks andtrailers and the like wherein it is desired to provide steps which canbe stored in a limited amount of verti' cal space, and wherein the stepsare manually extended to operative position when desired.

Folding steps of this nature have been heretofore provided in the priorart, and a typical example is illustrated in US. Pat. No. 3,291,255. Thefolding step arrangement as shown in this patent capable of being storedin a relatively small vertical space, but a principal disadvantage ofthis arrangement is the fact that considerable space isrequiredlongitudinally of the associated vehicle to receive the folding steparrangement in its stored position. In other words, when extended, thestep ar rangement is disposed longitudinally of the vehicle, and then isfolded up and slid into place in a longitudinal direction. Accordingly,in order to accommodate the folding step arrangement, it is necessary tohave a rather extensive longitudinal space available on the associatedvehicle. Many vehicles with which the present invention is intended tobe employed do not have sufficient longitudinally extending space foraccommodating this type of arrangement.

A further disadvantage of the construction as shown for example in theaforementioned U.S. Pat. is the fact that considerable friction isencountered when moving the step arrangement into and out of operativeposition. Additionally, no means is provided for positively retainingand holding the step arrangement in its stored position.

SUMMARY OF THE INVENTION In the present invention, a support means isprovided including a first portion adapted to be fixed to theundersurface of a vehicle or the like, the support means also includinga second portion which is swingably supported by the first supportportion.

The step means is in turn swingably interconnected with the secondportion of the support means. This arrangement enables the step means tobe folded into a very small vertical space and then to be swung throughan angle of approximately 90 so that in its stored position, the steparrangement is disposed substantially at a 90 angle with respect to thedisposition of the step arrangement when in its operative erectedposition.

Accordingly, in an arrangement wherein the steps in erectedoperative-position extend longitudinally of the associated structuresuch as a vehicle or the like, the step arrangement extends laterally ofthe supporting structure or vehicle in a stored position. The steparrangement may be stored laterally of a vehicle closely adjacent to therear end thereof thereby eliminating the necessity of providingconsiderable space extending longitudinally of the vehicle for storingthe steps. In fact, the arrangement of the present invention enables afolding step arrangement to be stored in a very minimum oflongitudinally extending space with respect to an associated vehicle.

The swingable or movable portion of the support means of the presentinvention is mounted for movement about a fixed pivot axis and includesa part which is slid-able within an arcuate guide slot in the otherportion of the support means. This arrangement reduces to a minimum thefriction encountered upon movement of. the folding step arrangementbetween a stored and operative position.

Additionally, the overall construction of the-present invention enablesa very lightweight yet strong retractable folding step construction tobe readily manufactured.

A holding means is also provided for positively holding the folding steparrangement in its stored position, this holding means including aresiliently biased means readily permitting the steps to be moved fromthe stored position when so desired.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view showing asuitable support means such as the rear end of a vehicle beneath whichthe folding step arrangement of the present invention is supported;

FIG. 2 is an end view of the structure shown in FIG. l;

FIG. 3 is a sectional view taken substantially along line 3-3 of FIG. Ilooking in the direction of the arrows;

FIG. 4 is a view on an enlarged scale taken substantially along line 4-4of FIG. 2 looking in the direction of the arrows;

FIG. 5 is a sectional view taken substantially along line 5-5 of FIG. 4looking in the direction of the arrows;

FIG. 6 is a view partly in section taken substantially along line 6-6 ofFIG. d looking in the direction of the arrows;

FIG. 7 is a sectional view on an enlarged scale taken substanfiallyalong line 7-7 of FIG. 2 looking in the direction of the arrows andillustrating the steps in erected position;

FIG. 3 is a top perspective view illustrating the manner of swingablyinterconnecting the upper and lower side rails with a portion of thesupport means;

FIG. 9 is a sectional view taken substantially along line l -9 of FIG. 4looking in the direction of the arrows;

FIG. Ml is a bottom view illustrating a modified form of the inventionin stowed position;

FIG. 11 is asectional view taken substantially along line 1 1-1 1 ofFIG. it) looking inthe direction of the arrows;

FIG. 12 is a sectional view on an enlarged scale taken substantiallyalong line 12-12 of FIG. 10 looking in the direction of the arrows;

FIG. 13 is a sectional view taken substantially along line 1-13 of FIG.ll looking in the direction of the arrows and illustrating the foldingsteps in the down position; and

FIG. 14 is a top perspective view illustrating a portion of thestructure of this form of the invention. DESCRIPTION OF THE PREFERREDEMBODIMENTS Referring now to the drawings wherein like referencecharacters I designate corresponding parts throughout the several views,reference numeral It indicates any suitable supporting surface such asthe floor of a camper or the like to the underside of which it isdesired to secure the retractable folding steps.

The support means for the retractable folding steps includes a firstportion indicated generally by reference numeral 12 comprising a sheetof metal which is fixedly secured to the undersurface of member 10 by aplurality of nut and bolt assemblies M shown as being four in number andextending through suitable aligned holes provided in members 10 and 12.

As seen most clearly in FIG. 5, member 12 includes a depressed integralportion 15 which receives a headed pivot pin 16, this pivot pinextending through a first part 18 of a second portion of the supportmeans. As seen in FIG. 8, a pair of connecting rods Zll extend throughholes in member l8 and a similar member 24 having a headed pivot pin 26rigidly interconnected therewith.

The support member 12 also includes an integral depending arcuateportion 30 having an arcuate slot 32 formed through the bottom wallthereof as seen most clearly in FIGS. 4 and 9. This slot includesopposite closed ends 36 and 38.

The shank of headed pin 26 extends upwardly through slot 32, and thehead of pin 26 is larger than the slot 32 whereby pin 26 is supported bythe depending portion 36 and the slot 32 guides movement of pin 26 andthe associated part 2d of the second support means portion.

It is apparent that the second portion of the support means is swingablymounted with respect to the first portion of the support means and isswingable about the fixed axis of pin 16. As seen most clearly in FIGS.'7 and 8, the upper surface of member 18 is provided with a centraldepressed portion 40 to provide clearance with the portion of member 12whereby the second portion of the support means can freely swing aboutthe axis of pivot pin 16.

As seen most clearly in FIG. 8, the step means of the present inventionincludes a pair of upper side rails 50 and 52 the upper ends of whichare rigidly secured as by welding or the like to the outer ends of oneof the connecting rods 20. These upper side rails are offset above thepivot axis of the associated connecting rod, this connecting rod beingfreely rotatable within the holes through which it extends in members 18and 24 whereby the upper ends of the upper side rails are swingablyconnected to the support means.

A pair of spaced lower side rails 54 and 56 are rigidly secured as bywelding at the upper ends thereof to the opposite ends of the other ofthe connecting rods 20. These lower side rails are offset below thepivot axis of the associated rod which is freely rotatable within theholes through which it extends in members 18 and 24.

As seen in FIG. 2, the lower or opposite ends of side rails 50 and 54are interconnected with one another by a base member 60. This basemember is pivotally interconnected at 62 with lower side rail 54, and ispivotally interconnected at 64 with the upper side rail 50. The lowerends of the other pair of side rails 52 and 56 are similarlyinterconnected with one another by a similar base member, these basemembers being adapted to rest upon the ground or the like for supportingthe lower end of the retractable folding steps when in operativeposition.

As seen most clearly in FIGS. 4 and 6, the step means of the presentinvention includes a first plurality of support rods 70 supportedbetween the lower side rails 54 and 56. These support rods are ofgenerally circular cross-sectional configurations and are disposedwithin cutouts formed in the upper edges of the lower side rails so thatapproximately one-half of the cross-sectional dimension of the supportrods is disposed within each cutout, the support rods then beingsuitably secured in place as by welding or the like.

A further plurality of support rods 72 are secured to the lower edges ofthe upper side rails 50 and 52. These support rods are also of generallycircular cross-sectional configuration and are disposed within cutoutsprovided in the lower edges of the upper side rails so thatapproximately one-half of the cross-sectional dimension of the rods isreceived in each cutout. The support rods are suitably secured in placeas by welding or the like. I

A plurality of similar steps 74 are provided, these steps being ofgenerally rectangular plan configuration as seen in FIG. 4, each of thesteps includes a depending flange 76 formed about the peripheral edge ofthe step. The support rods 70 and 72 extend freely through suitableholes provided in opposite parts of the flange 76 of each of the stepswhereby the steps are movably interconnected to the rods 70 and 72 andthereby to the upper and lower side rails. The steps form aparallelogram arrangement with the associated upper and lower side railsso that the steps remain parallel with one another at all positions ofthe side rails. Members 18 and 24 as well as the base members secured tothe opposite ends of the side rails also remain parallel with the stepsat all times so that the steps are maintained in substantially ahorizontal plane during normal use to enable them to be utilized assteps.

The lower edge of each of the upper side rails is provided with aplurality of spaced cutouts 80 formed therein, these cutouts beingadapted to receive a support rod 70 secured to the lower side rails whenthe side rails are pivoted into the stored position as seen particularlyin FIG. 6.

Similarly, the upper edges of each of the lower side rails are providedwith a plurality of spaced cutouts 82. Both the cutouts 80 and 82 aregenerally semicircular in cross section. The cutouts 82 are adapted toreceive the connecting rod 20 as well as the various support rods 72secured to the upper side rails when the apparatus is in its storedposition as seen in FIG. 6.

Accordingly, with the arrangement described, the retractable foldingstep arrangement can be folded into the position shown in FIG. 2 whereinit occupies a minimum of vertical space. As seen in FIG. 2, the steparrangement is disposed laterally of the supporting structure. When itis desired to move it into operative erected relationship, theretractable steps are moved from the dotted line position shown in FIG.1 in the direction of the arrows into the phantom line positionillustrated in that figure whereupon the side rails may be droppeddownwardly into the position shown in FIGS. 7 and 8 so that the stepswill assume the erected operative relationship.

Referring now to FIG. 3, a holding means is provided for holding thefolding steps in stored position. This holding means includes aresilient portion disposed substantially parallel with the under surfaceof member 10 and including an outer shoulder portion 92 adapted toengage the adjacent lower side rail of the step means to hold the stepmeans in stored position. A sloping cam surface 94 is provided on theend of member 90 so that the folding means will be automatically biaseddownwardly into the phantom line illustrated in this figure when thefolding steps are swung toward the stored position.

Portion 90 of the holding means joins with an i war upwardly extendingportion 96 which in turn is integral with a portion 98 secured to theundersurface of member 10 by a plurality of nut and bolt assemblies 100.

Portion 98 of the holding means joins with a portion 102 which extendsdownwardly and terminates in an end portion 104 rigidly affixed as bywelding to the previously described portion 5%).

It is apparent that in the position shown in solid lines in FIG. 3, theholding means will retain the folding steps in the stored position. Whenit is desired to move the steps into erected position, the portion 90may be manually moved downwardly so that the folded steps can clear theshoulder 92, whereupon the steps may be swung through an angle ofapproximately 90 and then lowered downwardly into erected operativeposition.

When it is desired to return the steps to stored position, the siderails are swung upwardly and then turned through an angle ofapproximately 90 to return to the stored position shown in FIGS. 1, 3and 4.

Referring now to FIGS. 1014 inclusive, a modified form of the inventionis illustrated. This embodiment is similar in many respects to thatpreviously described. and similar parts have been given the samereference numerals primed.

The manner in which the folding steps are secured to the movable portionof the support means in this form of the invention is simplified. Thelower end of the headed pivot pin 16' is provided with a tubular portionreceiving an end of one of the connecting rods 20' whereby thisconnecting rod is journaled within this tubular portion. The lower endof the headed pivot pin 26 is disposed between and rigidly affixed as bywelding or the like to a pairof parallel plates 112 and 114. Theseplates have aligned holes formed therethrough for receiving theconnecting rods 20' which are thereby journaled for rotation within thetwo plates.

The folding step portion of this form of the invention is substantiallyidentical with that previously described. The base members in this formof the invention are simplified. A pair of similar base members areprovided, each of the base members being of generally U-shapedcross-sectional configuration and having opposite generally parallel legportions, these leg portions receiving opposite ends of pivot pins 122and 124 which aresecured respectively to the lower ends of the lowerside rails and upper side rails.

A modified holding means is provided in this form of the invention. Theholding means includes a generally U-shaped bracket secured to theundersurface of member 10 by a pair of screws 32. A holding pin isslidably mounted within suitable aligned holes provided in bracket 130.This pin includes an enlarged head 14-2 which is adapted to be manuallygrasped for operating the pin. A stop means 148 is provided at anintermediate portion of the pin and may comprise a cotter pin positionedwithin a diametrically extending hole formed through pin Mil. Theopposite end 150 of the pin is adapted to fit within oneof the U-shapedbase members 66) for retaining the apparatus in its stowed position asseen in M68. it) and 12.

A compression spring 152 is disposed in surrounding relationship to pinM0 and is interposed between bracket member 130 and the cotter pin 148for normally biasing pin Mil toward its lock position. When it isdesired to unlock the device the pin is simply manually withdrawnagainst the force of the spring whereupon the apparatus may be swunginto the desired position.

As this invention may be embodied in several forms without departingfrom the spirit or essential characteristics thereof, the presentembodiment is therefore illustrative and not restrictive, and since thescope of the invention is defined by the appended claims, all changesthat fall within the motes and bounds of the claims or that form theirfunctional as well as conjointly cooperative equivalents are thereforeintended to be embraced by those claims.

I claim:

ll. Retractable folding steps comprising support means including a firstportion adapted to be fixed to suitable means and a second portionmovably supported by said first portion for swinging movement about afixed axis, said first portion of the support means including guidemeans adjacent said fixed axis to guiding movement of the second portionof the support means with respect thereto, step means swingablysupported by said second portion of the support means about an axisperpendicular to said fixed axis, whereby the structure is adapted to befolded into a very compact arrangement, and yet may be readily extendedinto operative position.

2. Apparatus as defined in claim 1 wherein said second portion of thesupport means includes one part which pivots about said fixed axis and aspaced part which is slidably supported by said first portion of thesupport means.

3. Apparatus as defined in claim 1 wherein said guide means includes anelongated arcuate'slot formed in said first portion of the supportmeans.

4. Apparatus as defined in claim 3 wherein the ends of said slot areclosed to limit movement of the second portion of the support means withrespect to the first portion of said support means, said second portionof the support means including a part slidably disposed within saidslot.

5. Apparatus as defined in claim l wherein said step means includes apair of upper side rail means and a pair of lower side rail means, and aplurality of steps pivotally interconnected with said pairs of upper andlower side rail means to provide a parallelogram arrangement.

6. Apparatus as defined in claim 5 including support rods connectedbetween said upper side rail means and additional support rods connectedbetween said lower side rail means, said steps being movablyinterconnected with said support rods, said upper side rail means beingoffset above the associated support rods, said lower side rail meansbeing offset below the associated support rods.

7. Apparatus as defined in claim a wherein each of said upper side railmeans and said lower side rail means includes a plurality of cutoutsformed therein for receiving certain ones of said support rods. Y

8. Apparatus as defined in claim 1 including holding means for holdingthe retractable folding step arrangement in its stored position.

9. Apparatus as defined in claim 1 wherein said second portion of thesupport means includesa tubular portion journaling a member connectedwith said steps.

Ml. Apparatus as defined in claim 1 wherein said second portion of thesupport means includes a depending member rigidly connected with platemeans, and a pair of members interconnected with said steps andjournaled by said plate means.

ll. Apparatus as defined m claim 1 wherein and steps include a pair ofupper side rail means and a pair of lower side rail means, said stepsbeing pivotally connected with said pairs of upper and lower side railmeans, and base members pivotally connected with the lower ends ofadjacent upper and lower side rail means, each of said base membersbeing of generally U-shaped cross-sectional configuration.

12. Apparatus as defined in claim 1 including holding means for holdingthe retractable folding step arrangement in its stored position, saidholding means including a support bracket, 21 pin slidably supported bysaid support bracket, and resilient means for normally biasing said pinin one direction.

